Time fuse for projectiles



Aug 3, E943. F. DELAY I TIME FUSE FOR PROJECTILES 4 Sheets-Sheet l` Filed Feb. 28, 1940 Aug., 3, 1943. F. DELAY 2,325,749

TIME FUSE FOR PROJECTILES Filed Feb. 21a, 1940 4 sheetswsheet 2 A X5 mgl@ Aug. 3, 194% F. DELAY 2,325,749

\ TIME FUSE FOR-PROJECTILES Filed Feb. 25, 1940 4 Sheets-5heet 3 Aug., 3, 19423. F. DELAY TIME FUSE FOR PROJECTILES Filed Feb. 1940 4 Sheets-Sheet 4 Patented Aug. 3, 1943 rosa Foa PRoJEoTmEs Fernand lDelay,(Sex'icva, Switzerland, assigner of one-half'to Cesar Adolphe Schmitt, Geneva,

Switzerland Application February 26, 1940, Serial No. 320,911

VIn Switzerland August 1S, 1939 plify the construction of time-fusesand'to avoid The present invention relates to a'tim'e-fuse for rotational proiectiles of the spring drivenV clockwork type in which the regulation* of the time ofignition takes place simultaneously with the winding oi the driving spring and wherein self rotation of the clockwork isI arrested` by centrifugal means so long as the Vprojectile is' not fired off.

In known time-fuses of thisrtype, the following arrangement is found: The driving' spring is wound on a barrel shaft pivotally supported in two bearings provided, on the one side, by a part of the clock work-calledthe movable frame and, on the other side, by a part of said-workcalled the frame. This arrangement complicates the manufacture and,rbesides presents a considerable disadvantage'due to the tolerancesof manufacture` susceptible to-provoking a faulty alignment of the two bearings in question.

Other time fuses of the common typecornprise a bung mounted to rotate upon a fixed-'axle rigid with the body part of the fuse. Sucharrangements are liable tothe'same inconveniences in consequenceY of the clearance z-.llot'tedto'-Ut-he' tolerance'of 1nanufacture. The said'construe#I tions are apt to'cause av faulty alighmentewith respect to the clock work because the"org'an 'transmitting the driving forceahd'consisting of an' eiiternal o-rinternal' 'gear' wheel isf made integral'with Vthe" barrel shaft or 'with'the bung of the driving spring.

Another disadvantage inherntt'alihst'very time-fuse'of the citedtypresidsiiithe fact thatthe movable frame of the clocl'worlei'pbn rotation of which the setting-up'oftliei'giition time and, simultaneously,` the winding-upY ofthe driving spring take place, affords'nb stop-for limiting the reciprocating angular displacements on both sides of the neutralwor aero position. @wing to this deciency, the clock works are often subjected to irremediable deterioration which occur, for instance, in the case of faulty manipulation during Aassembling in-the work shop and, in particular,before introducing Ythe clock work into thebody partof the fuse: As-generallyused the clockl work may be 'indirectly protected against injury after itsrassernbling with'the body part ofthe fuse by reason of stopsor--likemeans provided 'for this purpose-on said bodypart, but owing tothe mentioned tolerances Iof manufacturasuchrmeanscannotfgive arguarantee of efficient l protection even after 'assemblingoff the the above cited inconveniences.v g

According tothe invention, the timeeiuse comprises in combination a hollow fuse body threaded to the projectile, a cap turnable on said body and carrying' awinding key, acase fixedly mounted in said body, an axial framecarryng the clockf work, said frame being rotatably mounted in said case and engaged by ,said key'l so as to entrain the arrested clockworkin arotatory movement about the axis of the projectile vupon turning said cap, an4v axially disposed central guide shaft formed'i'ntegralfwith said frame and terminating in a percussion' point,y an annular vbarrel Vsurrounding said` shaft and housing the driving springsaid barrel'being secured to said case and having attached thereto oneA end orf the driving spring, a springv pressed' primer slid'able on said shaft towards saidrpercussionipoint, means actuatable by centrifugal force for normally holding said primeraway from-said percussionA point, a bung for thedriving'spring' rotatably-mounted on said shaft andA having iixed thereto the other end of saidA spring, said bung being,-V oniv the 1 one hand, connectedto saidl clockwork-for effecting simultaneously the winding of'said spring and the regulation of theig'nition-*ti'me byman'sof said turnable cap," winding keyandro'tatable frame and for driving afterwards said clockwork under the action lof the i driving forceA4 stored in said springwhe'n 'said worlhas been released for self rotation to control theangular'displacernent of said'bung during" the flightoi the; projectile, said bung'being also adapted to coopVU atdwith the primer to-allowf a' sudden4 advancing" of said primer towards theI percussion-point during self rotation of the clockworhand mean's'onzthe case and frame', respectively, for limiting the 'angular displacementof the frame; `in either ndirection thereby protecting Ythe ciocliwcnkN 4againstfdeterioiati'on during assembling of the' 1fuse.

Furnier objects and advantages or thel rmprovedconstruction` will be apparent ironiv'the following description, reference being' had to' the accf'rnpanying drawingswhichillustrate, by 'way of example, one nen'ibodinient of ltheinvention. Figure l is ejidalV sectionvshowing'the timefuse in itsnpositionofrest,V Figure 2 is an axial section showing the tiniefuse in thek position after the settinglunY o fthe ignition time, andY Figure 3 is a similar section showing said fuse ready for explosion.

Figures 4 ando aregsecti'onstaken along the lines 4=4-and-5e15 of: Figure l:

Figure 6 is an elevation and Figure 7 is a plan view of a detail.

Figure 8 is an axial section of another detail.

Referring in detail to the drawings, I represents the body of a time-fuse having screw thread Ia by means of which it may be secured to the projectile not represented. Said body is 'constructed of two portions Ib and ic which are united at their inner ends by means of a screw thread Id and a screw Ie. The body I carries on its top a cap 2 mounted to rotate thereon and having a graduation 2a displaceable in relation to a reference mark provided on said body. The cap 2 presents also a winding key 3 the lower end of which aiords a shoulder having two slots disposed diametrically opposite each other. Y

Within the body I is iixedly mounted a case 5 constructed of a cylindrical socket 5a and a mounting plate 5b rigid with said socket and resting on a mounting plate If of the body I. The said case houses a rotatable frame of the clock work, which frameincludes a block 1 having fixed thereon anupper'mounting plate 8, a disk 9 and a shaft I5 forming at its free end the percussion point II. To the mounting plate 8 are iixed two fingers I2 engaging the slots 5 of the above mentioned winding key.

I3 represents a driving spring located in a barrel I4 which may be prevented from rotating by a finger I5 of the case 6. The saidspring is fixed at one end to the barrel drum and at the other end to a hook I3 of a bung I1 (see Figures 6 and 7) rotatably mounted on the shaft I0. Said bung presents at its upper end a projection I8 engaging a slot provided in a plate I9 which thus partakes of the rotation of the bung. The plate I9 is secured to a socket 20 forming an internal gearwheel 2| meshing with a pinion 22 of a clock work,'said pinion being pivoted on .the one side in the block 1 and on the other side in the disk 9. On the upmr end of the wheelwork is mo-unteda regulating balance wheel 34 which is held stationary bymeans of lock bolts not represented, said bolts being displaceable under the influence of centrifugal force.

IThe lower end of the bung. I1 affords a plate 33having a slot 23 which may be obtained by upsetting a piece of material forming a beak 24.

25 represents a priming holder slidable along the shaft I0 andsubjectcd to theaction of a spring 25 bearing against the body I and tending to shift said priming holder upwards. The upper extremity of the priming holder alfords a tail 21 and the lower extremity thereof carries a hollow plug or percussion cap 3l adapted to receive the priming 32 stored i therein. Said priming holder cooperates Ywith two radial lock bolts'28 subjected to the action of centrifugal force, one of said bolts being represented in theFi'gures l to 3. Also the plate 33`of the bung I1 cooperates with a radial lock bolt 29 responsive to centrifugal force. i

Figure 1 shows the time-fuse in the position of rest. The driving spring I3 which is slightly wound up acts upon the bung I1 so as to cause the beak 24 thereof to engage in a slot 30 provided on the inner extremity of the lock bolt 29.

Said bolt is maintained in the position shown, first by itsspring the effect of which is not counter-acted by the eiect of centrifugal force, and then, so long as the setting-up of the ignition time to at least a quarter `of 'a' second `has not taken place, by the pressure'of the beak 24 which prevents said bolt from becomingdisplaced outwardly under the inuence of sudden shocks or the like. The tail of the priming holder 25 extends through superposed holes of the two mounting plates 6b and If to assume a position opposite the slot 23 of the bung plate 33; it will, however, be prevented from traversing said slot by the action of the two lock bolts 23 which hold the priming holder against the pressure of the spring 2B etc. Besides, owing to the fact that the lock bolt 29 closes the slot 23 the tail is retained against traversing said slot even if the lock bolts 28 were not in the normal position.

To effect the setting-up of the ignition time, for instance to 20 seconds, the cap 2 will be rotated about half a revolution as shown in Figure 2. The escapement of the clock work is held immovable by its lock bolts, and pinion 22 is thus prevented from rotating about its own axis; it partakes, however, of the rotation of the block 1 about the longitudinal axis of the fuse and thereby entrains the internal gear wheel 20-2 and the bung I1 which in turn winds up the driving spring. The beak 261 of the bung becomes disengaged with the slot ofthe lock bolt 29, and the `slot 23 of the pla-te 33 will be removed about an angle of with resp-ect to the tail 2'I of the priming holder 25.

supposing that the projectile be fired on, the lock bolts of the balance wheel and the lock bolts 28 and 29 will then be shifted outwardly unde` the iniiuence of centrifugal force; pinion 22 will be allowed to` rotate about its own axis and the driving spring thus expands until the slot 23 assumes a position above the tail 21. In that moment, the priming holder 25 will be shifted upwards under the action of spring 26 whereby its tail traverses the slot 23; the percussion cap containing the priming thus comes into contact with the percussion point II; the priming will be ignited and the projectile explodes. supposing that prior to firing oi the projectile, the setting-up of the ignition time has not been effected or a faulty adjustment aiming less than a quarter of a second has taken place; in that case the projectile can not explode when leaving the gun mouth because the beak 24 still engages the slot 30 thereby preventing the lock bolt 29 from becoming displaced under the influence of centrifugal force.

Moreover, it is to be seen that the mounting plate 8 affords a stop 35 (Figure 4) cooperating with a back stop 36 set in a slot 31. (Figure 1) provided on the upper rim of the socket 6a of the case 6. The said stops cooperate in the following manner: D uring assembling and testing, the case 6 will be placed into the body ofthe fuse; then, in said case the bung I1 and the driving spring will be engaged with the barrel I4, whereby the beak 24 bears against the lock bolt 29 with a slight pressure given to the driving spring; iinally, the plate I9, socket 20 and block 1 will be placed into the case 6, whereby the stop 35 will assume a position above the slot'31 of the case as shown in Figure 4, and the back stop 36 will be positioned into the slot 31. From that moment, the stop 35 bears against the back stop 36 owing to the action of the driving spring and prevents the latter from complete expansion even when removing the lock bolt 29 for withdrawing the case 6 and its contents from the body of the fuse. Besides, in the case of faulty manipulation occurring when turning the mounting plate 8 involuntarily in the direction of winding-up the driving spring, it will be possible to turn the same only about a revolution owing to the stop 35 which then reaches the backstop 36 to bear against the opposite side thereof; in this way, the driving spring is elcaciously protected against accidental overloading liable to demolish the wheelwork and particularly to buckle or break single teeth of the gear wheels.

I claim:

l. Time-fuse for rotational projectiles of the spring driven clockwork type. in which the regulation of the time of ignition takes place simultaneously with the winding of the driving spring and wherein self rotation of the clockwork is arrested by centrifugal means so long as the projectile is not fired off, said fuse having in combination a hollow fuse body adapted to be threaded to the projectile, a cap turnable on said body and carrying a Winding key, a case Vfixedly mounted in said body, a clockwork, an axial frame carrying the clockwork, said frame being rotatably mounted in said case and engaged by said key so as to entrain the arrested clockwork in a rotatory movement about the axis of the projectile upon turning said cap, an axially disposed central guide shaft formed integral with said frame and terminating in a percussion point,

a driving spring, an annular barrel surrounding said shaft and housing the driving spring, said barrel being secured to said case and having attached thereto one end of the driving spring, a spring pressed primer slidable on said shaft towards said percussion point, means actuatable by centrifugal force for normally holding said primer away from said percussion point, a bung for the driving spring rotatably mounted on said shaft and having fixed thereto the other end of said spring, said bung being, on the one hand, connected to said clockwork for effecting simultaneously the winding of said spring and the regulation of the ignition time by means of said turnable cap, winding key and rotatable frame and for driving afterwards said clockwork under the action of the driving force stored in said spring when said clockwork has been released for self rotation to control the angular displacement of said bung during the flight of the projectile, said bung being also adapted to cooperate with the primer to allow a sudden advancing of said primer towards the percussion point during self rotation of the clockwork, and means on the case and frame, respectively, for limiting the angular displacement of the frame, in either direction thereby protecting the clockwork against deterioration during assembling of the fuse.

2. Time-fuse according to claim 1, said clockwork having a pinion rotatable about its axis as soon as the projectile has been red off and adapted to` partake of the rotation of said frame about the axis of the projectile upon turning said cap, said bung carrying at one end an internally toothed crown wheel meshing with said pinion, and forming at its other end a disk provided with a slot, said case carrying means actuatable by centrifugal force and adapted to close said slot so long as the projectile has not been fired off, and said primer forming a tail extending towards said disk and adapted to traverse the slot therein to allow sudden advancing of the primer towards the percussion point when said bung has been subjected to the control of the clockwork during the flight of the projectile.

3. Time-fuse according to claim 1, said case being provided with a slot at the top, and the means limiting the angular displacement of the frame comprising a stop on said frame and a back stop placeable into said slot after the positioning of the frame and clockwork into said case, whereby said stop bears against one side of said back stop to prevent the driving spring from complete expansion, and abuts against the other side of said back stop when turning the frame in the opposite direction upon winding said spring.

FERNAND DELAY. 

